1. Field of the Invention
The present invention relates to a static hydraulic pressure type continuously variable transmission in which a hydraulic pressure closed circuit is formed between a swashplate type hydraulic pump and a swashplate type hydraulic motor. 2. Description of the Prior Art
A static hydraulic pressure type continuously variable transmission of the type herein referred to has already been known as disclosed, for example, in Japanese Patent Publication No. 38,467/1984.
In such a conventional static hydraulic pressure type continuously variable transmission as described, a pump cylinder of the hydraulic pump is pressed rotatably slidably against a distribution board fixedly mounted on the motor cylinder of the hydraulic motor so that working fluids of the hydraulic pump and hydraulic motor are transferred through an oil path extending through their rotary sliding surfaces. Because of this, pressure oil is difficult to be prevented its leakage from between the opposed rotary sliding surfaces of the distribution board and the pump cylinder, such oil leakage may lead to deterioration of transmission efficiency.